<html>
<script>
function add(a,b){
	var n = 0;
	// var c = false;
	var c = 0;
	for( var i = 1; i != 0; i = i << 1) {
   		var _a = (a & 1 ) == 1;
   		var _b = (b & 1 ) == 1;
   		var _n = (_a ^ _b ) ^ c;
   		c = _a &  (_b | c ) | ( _b & c );
   		n = n | (_n ? i : 0);
   		a = a >> 1;
   		b = b >> 1;
	}
	return n;
}

alert( add(2,3));
</script>
</html>